This application is based upon and claims the benefit of German Patent Application No. 19918174.8 filed Apr. 21, 1999.
The invention pertains to a quick-fitting pipe union having an insert component and a socket component including a new and improved sealing element as well as to a process for assembling a quick-fitting pipe union.
Quick-fitting pipe unions of the type that is being addressed here are known. They serve for connecting two hollow objects that are capable of accommodating a medium that is flowing through them. They comprise, in essence, an insertion component and a socket component, whereby the insertion component is introduced into the socket component in order to make the connection. Quick-fitting pipe unions also have sealing elements in order to ensure a leak-proof connection between the insertion component and the socket component. These sealing elements are preferably constructed in annular form and are usually pushed over the insertion component before the insertion component is introduced into the socket component. However, it is also conceivable that the sealing element is introduced into the socket component before the insertion component is pushed into the socket component.
Sealing elements are known with many different sorts of cross-sectional contours, e.g. ring-shaped and polygon-shaped including triangular-shaped or square-shaped contours. It has been found that the quick-fitting pipe union becomes leaky under some operating conditions and exchange of the quick-fitting pipe union or, at least, of the sealing elements is required.
The objective of the invention is therefore to create a quick-fitting pipe union that does not exhibit this disadvantage.
This objective is accomplished by a quick-fitting pipe union that has a sealing element which comprises two lips that extend out from an elastic connecting section. The quick-fitting pipe union excels by virtue of an annular sealing element with an elastic connecting section and two lips that extend outward from the connecting section. Loss-free, (i.e. leak-free) sealing between the insertion component and the socket component of the quick-fitting pipe union is possible as a result of the specific configuration of the sealing element of the quick-fitting pipe union. In conventional seals with elastomeric sealing elements, one of the most decisive parameters for freedom from leakage of the connection is the pressure deformation remnant (DVR) or, respectively, the relaxation of tension and the restoring force; however, in the case of the sealing element that is presented here, it can be guaranteed that the two lips of the sealing element are connected to one another in such a way via the elastic connecting section that the sealing element makes contact with the insertion component or, respectively, the socket component in an elastically springy manner even when the quick-fitting pipe union has been opened and closed repeatedly.
In a preferred example of an embodiment of the quick-fitting pipe union, the connecting section describes, in essence, a circular arc when considered in cross-sectional form and in the uncoupled state of the quick-fitting pipe union. Very good springy forces can be achieved within the sealing element as a result of the circular arc shaped connecting section; hence this sealing element can be compressed in an elastically springy manner when closing the quick-fitting pipe union without the occurrence of plastic deformation that would lead to permanent deformation of the sealing element and thus leak-free sealing of the quick-fitting pipe union would not be guaranteed when opening and re-closing the quick-fitting pipe union.
The feature is provided in a preferred example of an embodiment of the quick-fitting pipe union that the circular arc extends over an angle of 200xc2x0 to 360xc2x0 in the situation in which the quick-fitting pipe union is uncoupled. This large arc of the connecting section guarantees high elasticity of the two lips of the sealing element even after repeated actuation of the quick-fitting pipe union.
A preferred example of an embodiment of the quick-fitting pipe union excels by virtue of the feature that the two lips stand out at an essentially obtuse angle, preferably at right angles, from the ends of the connecting section. An especially large separation thereby arises between the two lips so that these lips can also span a large sealing region.
A further preferred example of an embodiment of the quick-fitting pipe union excels by virtue of the feature that one lip is bent in the situation in which the quick-fitting pipe union is uncoupled. The curved lip is bent back again when closing the quick-fitting pipe union and is characterized by high restoring forces that permit especially good sealing action.
A further preferred example of an embodiment of the quick-fitting pipe union has a groove, which runs in an annular manner, in the socket component and a first oblique projecting region, which runs in an annular manner, in the insertion component. In the situation in which the quick-fitting pipe union is closed, one lip of the sealing element supports itself on the base of the groove of the socket component and the other lip supports itself on the first oblique region of the insertion component. In the case of a quick-fitting pipe union that has been completely closed in an improper manner, the process of pushing the insertion component out of the socket component is rendered especially favorable as a result of this configuration of the surfaces of the insertion component or, respectively, the socket component and, as a result, the correct positioning of the insertion component in the socket component is simultaneously indicated to the user.
A retaining element is assigned to the quick-fitting pipe union in a further preferred example of an embodiment of the invention, whereby the retaining element supports itself on a recess in the socket component and on the first oblique region of the insertion component in the situation in which the quick-fitting pipe union is uncoupled. The retaining element serves for axially fixing the quick-fitting pipe union in position when introducing the insertion component into the socket component. In the situation in which the quick-fitting pipe union is closed, the retaining element, which is preferably configured in an annular shape, supports itself on the first oblique region of the socket component and on a second oblique region of the insertion component.
In a further example of an embodiment of the quick-fitting pipe union, the surfaces of the insertion component and of the socket component are configured and optimized with respect to one another in such a way that, in the situation in which the quick-fitting pipe union is not closed completely, the insertion component is pushed out of the socket component as a result of the spring-like action of the sealing element. For this purpose, the surface of the insertion component or, respectively, of the socket component has various oblique regions and grooves as already described.
A preferred example of an embodiment of the quick-fitting pipe union excels by virtue of the feature that the medium, which is flowing through the quick-fitting pipe union, can be present in various states of aggregation. The medium can be a liquid, preferably a refrigerant such as R12, R134-a, or a hydraulic oil e.g. ATF (automatic transmission fluid), Pentosin, or another oil (engine oil, gear oil) or fuel (automobile engine fuel, Diesel engine fuel, kerosene) or water or a similar fluid. However, the quick-fitting pipe union can also have a gaseous medium flowing through it, preferably air, carbon dioxide, propane or isobutane.
The objective is also accomplished by means of a process for assembling specific components. When assembling the quick-fitting pipe union, the sealing element is first pressed into the groove in the socket component by means of a preferably rod-shaped tool that is also termed an installation mandrel. The sealing element supports itself on the base of the groove of the socket component and is axially fixed in position as a result. The insertion component is then introduced into the socket component.